Optical couplers for light guides permit functional interconnection of different light guides (also referred to herein as waveguides or light pipes). Broadly, such couplers can include ones used for optical communication (e.g., digital data encoded into light pulses) as well as ones used for distributing illuminating light, and the design and considerations that go into each type can be very different. Vehicle interior lighting may utilize these latter types of couplers to distribute light from one or more sources into different locations of the vehicle for such purposes as feature or area lighting. See, for example, U.S. Pat. Nos. 6,419,379 and 6,234,439 which disclose the use of waveguides for light distribution within a vehicle.
One use for an optical coupler in a vehicle lighting application is disclosed in U.S. Pat. No. 7,027,691, in which a light coupler is used to optically couple light from a plurality of light sources into an optical fiber. In a non-automotive application, U.S. Pat. No. 4,961,622 discloses an optical coupler having a housing in which are disposed optical elements that direct light coming into the housing at a first end via a first optical fiber into a plurality of optical fibers that exit the housing at a second end.
Unlike the more flexibly type of optical fibers shown in U.S. Pat. No. 4,961,622, automotive applications often involve the use of rigid acrylic or other transmissive waveguides that route light underneath or along vehicle interior trim components, requiring lengths and bends for which molding or extruding of the overall waveguide as a single component might not be the most flexible or cost effective from a manufacturing standpoint.